Latch needle for knitting machines

ABSTRACT

A steel latch needle for knitting machines, having a needle foot which is coated with, or constructed wholly or partially of, shock-absorbent material, for cushioning the engagement of the needle foot with the reciprocating elements of the knitting machine during operation.

United States Patent Berentzen 51 Oct. 24, 1972 [54] LATCH NEEDLEFORKNI'ITING [56] References Cited MACHINES [72] Inventor: HardoBerentzen, Ebingen/Wurt- UNITED STATES PATENTS temberg, Germany 822,4016/1906 Sturtevant ..66/123 Assignees: Gm & I Beyer X Beckert NadelfabrikCommandit- Gessel I i Ebingen/wumemben, FOREIGN PATENTS OR APPLICATIONSGennany 571,976 10/1958 Belgium ..66/!23 [22] Filed: June 4 19711,145,150 3/1969 Great Britain ..66/123 [21] Appl. N 149,969 PrimaryExaminer-Ronald Feldbaum Attorney-Allison C. Collard [30] ForeignApplication Priority Data CT June 15, 1970 Germany ..P 20 29 440.0 [57]ABS W a A steel latch needle for knitting machines, having a needle footwhich is coated with, or constructed wholly or partially of,shock-absorbent material, for [52] US. Cl. ..66/123 cushioning theengagement of the needle foot with the [51] Int. Cl. ..D04b 35/02reciprocating elements of the knitting machine during [58] Field ofSearch ..66/121, 123, 124 operation,

1 0 Claims, 12 Drawing Figures LATCH NEEDLE FOR KNITTING MACHINES Thepresent invention relates to latch needles for knitting machines, and inparticular, to a latch needle having a shock-absorbing needle foot.

Modern knitting machines operate at very high speeds. As a result, theacceleration and deceleration forces therein create vibrations whichlead to premature fatigue and breakage of the needle hook and latchbearings, and deformation of the needle shaft.

Accordingly, the present invention provides a latch needle for knittingmachines having a needle foot which engages the needle reciprocatingelements of the knitting machine and thereby reciprocates the latchneedle during operation. A layer of shock-absorbent material is disposedover the surface of the needle foot in order to cushion the engagementof the needle foot with the reciprocating elements of the machine duringoperation, and thereby prevent damage to the latch needle elements. Theneedle foot may be substantially rectangular'shaped, or dove-tailshaped, and have a cap or collar constructed of the shock-absorbentmaterial disposed over its surface. The needle foot may be constructedof two separate members affixed adjacent one another on the shaft of thelatch needle, having either a divided cap of shock-absorbent materialdisposed over the needle foot, or a strip of the shockabsorbent materialdisposed between the members. The needle foot and the layer ofshock-absorbent material may also be formed as an integral unit so thatthe needle foot is constructed either partially or wholly of theshock-absorbent material.

It is therefore an object of the present invention to provide a latchneedle in which damaging vibrations and forces are minimized.

It is another object of the present invention to provide a latch needlewhich is simple in design, easy to manufacture, and efficient andreliable in operation.

Other objects and features of the present invention will become apparentfrom the following detailed description considered in connection withthe accompanying drawings which disclose several embodiments of theinvention. It is to be understood, however, that the drawings aredesigned for the purpose of illustration only and not as a definition ofthe limits of the invention.

In the drawings, wherein similar reference characters denote similarelements throughout the several views:

FIG. I is a side view of a latch needle constructed in accordance withthe present invention, shown without a layer of shock-absorbent materialdisposed on the needle foot;

FIG. 2 is a side view of the latch needle of FIG. 1, showing a layer ofshock-absorbent material disposed thereon in the form of a cap;

FIG. 3 is a side view of the latch needle of FIG. 1 showing a layer ofshock-absorbent material disposed thereon in the form of a collar.

FIG. 4 is a side view of another embodiment of the present invention, inwhich the needle foot is constructed of a pair of members affixed to theshaft of the needle adjacent each other, and a layer of shock-absorbentmaterial is constructed in the form of a cap having two compartments forreceiving the members;

FIG. 5 is a side view of the embodiment of FIG. 2, in which the needlefoot is provided with an aperture and the cap of shock-absorbentmaterial is provided with a projection received by the aperture in orderto secure the cap on the needle foot;

FIG. 6'is a side view of another embodiment of the present invention, inwhich the needle foot is dove-tail shaped, and a layer ofshock-absorbent material is disposed over the needle foot in the form ofa cap whose interior surface conforms to the shape of the needle foot;

FIG. 7 is a top planar view of the latch needle shown in FIG. 6;

FIG. 8 is a side view of another embodiment of the present invention, inwhich the needle foot and the layer of shock-absorbent material are anintegral unit, and wherein the needle foot is secured in a recessprovided in the needle shaft;

FIG. 9 is a top plan view of the embodiment of FIG. 8;

FIG. 10 is a cross-sectional view of the needle foot taken along section8-8 of FIG. 8;

FIG. 11 is a side view of the latch needle shown in FIG. 4, wherein alayer of shock-absorbent material is constructed in the form of a stripand is disposed between the members of the needle foot; and

FIG. 12 is a top plan view of the latch needle shown in FIG. 1 1.

Referring to FIGS. 1-3, there is shown steel latch needle 1 having ahook 2 and a latch 3. A needle foot 4, substantiallyrectangularly-shaped, is affixed to the shaft of the needle. The needlefoot projects into a needle guide passage provided in the knittingmachine, and engages needle reciprocating elements contained therein sothat the latch needle is reciprocated during operation. Needle foot 4 issurrounded by, or coated with, a layer of shock-absorbent material. Asshown in FIG. 2, the layer of material may be formed as a rectangularcap 5, or as a rectangular collar 6, as shown in FIG. 3, both of whichare slidably disposed over the needle foot, for engaging thereciprocating elements and absorbing the shocks produced by the machineand thereby preventing premature damage to the latch needle. Theshock-absorbent material may be of any suitable type, such as plastic,and may be applied by spraying needle foot 4 with thermoplasticmaterial, or by dipping the needle foot in liquid plastic. A suitablyshaped plastic sleeve may also be disposed over the needle foot as shownin the drawings.

The amount of shock absorption produced by the material will depend onthe thickness of the coating applied to the needle foot. However, evenif the thickness of the coating amounts to only tenths of a millimeter,as may be required by the needle thickness, the coating will absorb theshocks and prevent a substantial amount of premature needle damage. Ifthe coating is made thicker, or if the needle foot is constructedpartially or wholly of the shock-absorbent material, theshock-absorption will be increased.

The shock-absorption may also be increased by constructing needle foot 4from two members 4 and 4 affixed adjacent each other on the shaft of theneedle as shown in FIG. 4. The layer of shock-absorbent material is thenpreferably constructed as a rectangular cap divided into twocompartments by an additional vertically disposed member which isslidably disposed in slot 8 between members 4 and 4'. However, as shownin FIGS. 11 and 12, the shock-absorbent material may be constructed asstrip 12 and disposed between members 4 and 4' to produce an equivalenteffect.

In any of the previously described embodiments, the shock-absorbentmaterial may be secured in place on the needle foot by any suitablemethods. The material may, for example, be molded in position, shrunk onthe needle foot, or attached by means of a suitable adhesive. Referringto FIGS. 5 and 6, the layer of shock-absorbent material may also besecured to the latch needle by providing needle foot 4 with aperture 9which receives a rigid projection affixed to the inside of, for example,the cap shown in FIG. 2, to secure the shockabsorbent material to theneedle. Needle foot 4 may also be constructed in a dove-tail shape tosecure a cap provided with an interior shape which conforms to the shapeof the needle foot. The choice of any of these methods, however, is upto the individual manufacturer.

Needle foot 4 may also be constructed as an integral unit with the layerof shock-absorbent material. FIGS. 8-10 show needle foot 14, which isconstructed entirely of shock-absorbent material, rigidly affixed inrecess 14' provided in needle shaft'l. In this embodiment, the maximumamount of shock absorption will result during the operation of themachine.

While only several embodiments of the present invention have been shownand described, it will be obvious to those skilled in the art that manychanges and modifications may be made thereunto without departing fromthe spirit and scope of the invention.

What is claimed is:

1. In a latch needle for knitting machines, the improvement comprising;

a needle foot afiixed to the shaft of the latch needle,

for engagement with the needle reciprocating elements of the knittingmachine and thereby reciprocating the latch needle during operation, and

a layer of shock absorbent material disposed over the surface of saidneedle foot for cushioning the engagement of said needle foot with thereciprocating elements of the knitting machine during operation.

2. The latch needle as recited in claim 1, wherein said needle foot issubstantially rectangular in shape and wherein said layer ofshock-absorbent material is a rectangular cap disposed over said needlefoot.

3. The latch needle as recited in claim 1, wherein said needle foot issubstantially rectangular in shape, and wherein said layer of shockabsorbent material is a substantially rectangular-shaped collar disposedover said needle foot.

4. The latch needle as recited in claim 2, wherein said needle foot isprovided with a horizontally disposed aperture, and wherein said cap ofshock absorbent material is provided with a horizontally disposedprojecting member affixed on the inside surface thereof which isreceived by said aperture when said cap is disposed over said needlefoot, for securing said cap to the latch needle shaft during operation.V

5. The latch needle as recited in claim 1, wherein said needle foot issubstantially dove-tail shaped, and wherein said layer ofshock-absorbent material is a substantially rectan lar cap having aninterior surface conforming to t e shape of said needle foot disposedthereon.

6. The latch needle as recited in claim 1, wherein said needle footcomprises a pair of substantially rectangular-shaped members affixed tothe shaft of the latch needle adjacent each other, and wherein saidlayer of shock-absorbent material is a rectangular cap divided into twoseparate compartments for receiving said members of said needle foot.

7. The latch needle as recited in claim 1, wherein said needle footcomprises a pair of substantially rectangular shaped members afi'ixed tothe shaft of the latch needle adjacent each other, and wherein saidlayer of shock-absorbent material is disposed between said first andsecond members of said needle foot.

8. The latch needle as recited in claim 1, wherein the shaft of thelatch needle is provided with a recess, for receiving and securing saidneedle foot on the shaft, and wherein said needle foot is integrallyformed with said layer of material and is constructed entirely of saidshock-absorbent material.

9. The latch needle as recited in claim 1, wherein said layer ofshock-absorbent material is integrally formed with needle foot so as tocomprise a portion thereof.

10. The latch needle as recited in claim 1, wherein said shock-absorbentmaterial is plastic.

1. In a latch needle for knitting machines, the improvement comprising; a needle foot affixed to the shaft of the latch needle, for engagement with the needle reciprocating elements of the knitting machine and thereby reciprocating the latch needle during operation, and a layer of shock absorbent material disposed over the surface of said needle foot for cushioning the engagement of said needle foot with the reciprocating elements of the knitting machine during operation.
 2. The latch needle as recited in claim 1, wherein said needle foot is substantially rectangular in shape and wherein said layer of shock-absorbent material is a rectangular cap disposed over said needle foot.
 3. The latch needle as recited in claim 1, wherein said needle foot is substantially rectangular in shape, and wherein said layer of shock absorbent material is a substantially rectangular-shaped collar disposed over said needle foot.
 4. The latch needle as recited in claim 2, wherein said needle foot is provided with a horizontally disposed aperture, and wherein said cap of shock absorbent material is provided with a horizontally disposed projecting member affixed on the inside surface thereof which is received by said aperture when said cap is disposed over said needle foot, for securing said cap to the latch needle shaft during operation.
 5. The latch needle as recited in claim 1, wherein said needle foot is substantially dove-tail shaped, and wherein said layer of shock-absorbent material is a substantially rectangular cap having an interior surface conforming to the shape of said needle foot disposed thereon.
 6. The latch needle as recited in claim 1, wherein said needle foot comprises a pair of substantially rectangular-shaped members affixed to the shaft of the latch needle adjacent each other, and wherein said layer of shock-absorbent material is a rectangular cap divided into two separate compartments for receiving said members of said needle foot.
 7. The latch needle as recited in claim 1, wherein said needle foot comprises a pair of substantially rectangular shaped members affixed to the shaft of the latch needle adjacent each other, and wherein said layer of shock-absorbent material is disposed between said first and second members of said needle foot.
 8. The latch needle as recited in claim 1, wherein the shaft of the latch needle is provided with a recess, for receiving and securing said needle foot on the shaft, and wherein said needle foot is integrally formed with said layer of material and is constructed entirely of said shock-absorbent material.
 9. The latch needle as recited in claim 1, wherein said layer of shock-absorbent material is integrally formed with needle foot so as to comprise a portion thereof.
 10. The latch needle as recited in claim 1, wherein said shock-absorbent material is plastic. 